This training grant will offer Lorena M Siqueira M.D., a program of mentored research that will facilitate her development as an independent clinician-scientist. Dr. Siqueira is an experienced pediatrician with subspecialty boards in Adolescent Medicine. Her immediate objectives are to enhance her understanding of epidemiological research design and methodology, as well as the application of statistical methods, while focusing on the content area of tobacco use among adolescents. The initial period of this proposed training engages Dr Siqueira in formal course work towards a M.P.H in Epidemiology, strengthening her skills in statistical analyses, theories of research design and scale construction/modification. Applying statistical skills learnt in the classroom, Dr Siqueira will systematically analyze a data set collected by Dr. Judith Brook in three cities in Colombia (South America) in the first two years of this grant proposal. Tobacco has become a major health problem in Latin America and more people die there of non-communicable diseases, many of which are caused by tobacco, than of communicable diseases. Most disturbingly there appears to be an increase in smoking prevalence among Colombian teenagers mainly in urban areas. In her analyses Dr Siqueira will: 1) identify the unique risk and protective factors related to frequency of smoking and delinquency in Colombian youth, 2) examine potential interactions among assessed risk and protective factors and 3) evaluate the sequencing among the domains of family, personality, peers and culture. Beyond using Pearson correlations and regression analyses to determine significant risk and protective factors and their interactions, structural equation modeling (SEM) will serve as the method of analysis. To generalize formal coursework in the theories of research design and methodology as well as continue using her developing statistical skills, Dr Siqueira will work with Dr. Brook on the sixth phase of her recently NIH-funded longitudinal study examining the etiologic determinants of young adult drug use/abuse and the consequences of use on the individual?s functioning. Dr Siqueira will be an integral member of a research team proposing and shaping the measure and scales employed. Furthermore she will be actively involved in data collection and analyses. During the third and fourth years of this award, she proposes to use five previously collected waves of this data-set to answer questions about the relationship of childhood personality and parent attachment to stability of tobacco use in adulthood. The skills learnt and data analyzed will be used to develop a R01 application in year five, building on the findings that have emerged in these analyses of tobacco use. Her long term goals are to evaluate how know researchcan be applied to clinical settings, design more effective intervention strategies and conduct outcome research.